Kaitsekihid

Kaitsekihid is a term in Estonian that denotes protective layers that surround an organism or an object, serving as barriers against damage from the environment. The concept covers natural coatings produced by living tissues as well as artificial coatings applied in industry.

In biology, kaitsekihid include the plant cuticle, the exoskeletons of arthropods, seed coats, and the enamel or outer layer of teeth, as well as skin and its keratinized layers. These layers form through secretion by specialized cells and, in some cases, mineralization or cross-linking that hardens the coating.

Functions of kaitsekihid include reducing water loss, providing mechanical protection, serving as a barrier against pathogens, and aiding in camouflage or signaling. They can also impose trade-offs, such as reduced gas exchange or growth constraints when the layer is very thick.

In materials science, kaitsekihid refers to protective coatings applied to metals, ceramics, or polymers to improve corrosion resistance, wear resistance, or chemical stability. Common types include oxide films, polymeric coatings, and ceramic layers deposited by methods such as physical vapor deposition, chemical vapor deposition, or painting.

The study of kaitsekihid covers their development, composition, and performance across organisms and applications, as well as the methods used to analyze their structure and effectiveness.